In flat roof structures such as those which are commonly used on industrial buildings, problems arise when water leaks between the roof's surface and the building's interior walls. Not only does such leakage damage the building and its roof structurally, but also it can damage materials stored in the building's interior.
One remedy is to deploy air- or foam-filled, membrane-covered barriers, such as those taught in my pending U.S. patent application Ser. Nos. 13/385,400 and 13/987,485, in such a way that said barriers direct storm water towards the building's downspouts, as well as prevent it from gaining access to any of a roof's naturally-occurring recessed areas. Unfortunately, when gutters are used to collect storm water and then feed it into the downspouts, additional problems emerge. Typically, gutters clog easily and require constant maintenance.
Moreover, high winds can cause the roof membrane to rip, especially at its juncture with a building's walls. As is well known, high winds give rise to vertical forces which tend to lift the membrane off of a building's roof. Such forces occur at the roof's windward edge whenever an air flow across it collides with an upward flow of air formed as a horizontal air flow strikes the building's upwind side and is then redirected upwardly.
Also contributing to roof membrane failure is the fact that critical fasteners at the roof deck/exterior building wall joint are continually stressed by discordant movements between the roof deck, as it expands and contracts mostly horizontally, and the wall, which expands and contracts mostly vertically. Indeed, Kelly, in U.S. Pat. No. 6,006,482, teaches that it is the destabilization of these fasteners, when they are used to secure the roof membrane in place, which ultimately leads to roof failure.
However, rather than seeking remedies whereby roof membrane failure in general can be virtually eliminated, Kelly directs his focus elsewhere. Specifically, he concentrates on improvements which can be used to reduce the extent to which a roof is catastrophically removed during a blow-off. Towards such an end, he teaches that those fasteners otherwise utilized to secure the main roof membrane proximate with the upwind side of the roof deck's outer edge must be repositioned and calls for them to be separated from said outer edge by a wide span, the width of which is such that those portions of the roof's upwind side deemed most susceptible to blow-off lie within it. Furthermore, the main roof membrane, no longer attached to these most susceptible portions is to be simply loose laid across them; and a perimeter membrane, separately attached, is to provide weather proofing in its stead. Even the roof covering's substrate is to be reconfigured so as to accommodate a groove-like “interruption”. Disposed inwardly with respect to said most susceptible portions and extending both longitudinally and generally parallel to the outer edge of the roof's upwind side, each such “interruption” is provided to insure that, in the event of a roof blow-off, a relatively clean break occurs.
Nevertheless, the lack of any raised, membrane-covered barriers or the like to mitigate the impacts of storm water and/or wind on roof membranes suggests that, in prior art roof assemblies such as Kelly's, much has been missed that could have been utilized to substantially reduce the incidence of roof failure whether due to blow-off or otherwise.